How to tell the difference between polyester and silk - comparison image

How to tell the difference between polyester and silk

Before I got into the world of natural fabrics and trying to live in a more sustainable way, I never had the habit of reading clothing labels. I don’t think I have even stopped to ask myself ‘what is this made out of?’ Imagine my shock when I was going through old clothes.

So many of the pieces that I thought were made of silk, were in fact polyester or satin! The scariest bit was that I did not have to read the label to know that it was not made of silk, I just knew by looking at it and touching it.

So, why did I ever think that it was silk in the very first place?

It was through actively learning about different fabrics, reading countless labels that I can now (mostly) tell silk from polyester. This is what you should look out for.

What are the main differences between polyester and silk

Simply summed up, polyester is a synthetic material, affordable, low maintenance while silk’s natural and luxurious. Here’s a quick comparison chart to list out the main differences.

Comparison chart between polyester and silk:

Properties Polyester Silk
Origin Man made synthetic fabric that is petroleum based Protein fibres of the silkworm
Wrinkling and creasing Good resistance Wrinkles and creases easily
Texture and touch Soft, less smooth Smooth, soft
Drape when worn Flowy but does not drape as well as silk Follows contours of body, drapes luxuriously.
Shine of the fabric No change in the shine of the fabric despite the varying  angles and intensity of light on it Fabric gives off a gentle shine when light hits it at different angles, shade of fabric may even appear a different colour. Fabric looks more lively
Washing and drying Little maintenance needed. Machine wash and dry or even out in the sun Lots of tender care required. Dry cleaning or handwashing, air drying away from direct sunlight
Price Generally cheap and affordable Not too wallet friendly, an item associated with luxury
Weave of the fibre Even, symmetrical Natural fibres are rarely perfect, expect some imperfection and flaws in the weave
Patterns on reverse side of fabric Do not show through Patterns are seen on reverse side


What is polyester

Polyester is one of the most common synthetic material [link]. It is very much safe to say that all of us has at least 3 item in our homes that is made out of polyester.

How to tell the difference between polyester and silk - polyester suits
Vintage polyester suits from the 70s

Is polyester and satin the same thing

Polyester is a material, while satin is a type of weave. I will speak more about satin later, but for now – lets look at polyester

What material does polyester feel like?

Polyester feels almost like silk, and is often a good dupe for silk garments. It mimics the appearance and texture of silk. In fact, when made well, it can often be difficult to distinguish polyester from silk, especially if you are not familiar with the latter.

What is silk

Silk is an amazing textile made of natural protein fibres from silkworms. It is hypoallergic, breathable, soft, supple, I can go on and on. But here’s an entire post dedicated to what silk actually is [link]

How can you tell if fabric is real silk?

Let’s state the obvious first, the composition tag. But that’s not the only tag you should look out for, the next most obvious sign of silk’s authenticity, is the price tag. You should also look out for the weave of the threads, sheen of the fabric, the underside of the fabric.

Sidenote, silk and polyester burns differently too

Cost of silk

Silk is an affordable luxury piece, but if the price tag of a silk blouse is cheaper than a cotton tee, that is an obvious sign that it is not the real deal.

What is the difference in weave of polyester and silk

Polyester is synthetic and man made, or rather machine made. Machine’s production is prized for uniformity and this shows in the weave of a polyester fabric. The weave of polyester is symmetrical, uniform, in a sense – perfect.

Natural silk’s weave is like nature itself; minor flaws with variations and imperfections. If you have a chance, use a magnifying glass and take a look at both weaves for yourself!

How to tell polyester and silk apart in sunlight

The perfect weave of polyester means that light is reflected evenly, shining ‘white’ under any light. Silk’s relative imperfect weave produces a subtle sheen, with its lustre changing ever so slightly depending on the angle which light hits it.

You can even say that the colour of the silk garment changes slightly under different lighting conditions.

How to tell the difference between polyester and silk - sheen of silk under light
Look at how silk displays its sheen where light hits and looks like a darker shade where it folds.

The difference between the underside of polyester and silk fabric

Polyester generally has a matt underside, while silk’s top and underside are both shiny and silky smooth.

How to tell the difference between polyester and silk - comparison image
Left: Polyester has a matt underside which is distinctively different from the topside. Right: Silk has the same smoothness and sheen on both the top and bottom side

What fabric feels most like silk?

Sometimes you want silk, but not the hassle that comes with caring for it, when that happens, I go for satin polyester.

Before you gasp dramatically, I am not talking about garments. Gift pouches! If you want a touch of luxe without the price tag, a satin polyester giftbag will remind your recipient of silk without the price tag that comes along with it.

What is satin made of

Satin can be made of silk, polyester or even cotton. This is because satin actually refers to the weave, not a type of fabric. However, satin is usually associated with both silk and polyester. A polyester with satin weave comes closest to mimicking silk.

Is polyester satin breathable compared to silk satin

Regardless of the weave, polyester’s breathability does not outdo Silk’s. Silk has high moisture wicking properties that synthetic polyester is unable to replicate. A silk blouse on a humid day will always make you feel more comfortable that a polyester blouse.

Silk VS Satin lining fabric

All three of them, Silk, satin and polyester will all line garment effectively. Silk linings are luxurious, breathable, drape perfectly but costly. Satin or polyester linings are commonly used as it is much more affordable.

Most garments today are lined with synthetic satin fabric, but if you are tailoring a something for yourself, give silk linings a try!

How to tell the difference between polyester and silk - silk lining for wedding dresses
silk linings are synonymous with wedding gowns

Does polyester feel like silk pillowcase?

It may look and feel like silk initially, but a couple of minutes on a polyester pillowcase and you will be reaching for your silk pillowcase instead. Polyester pillowcases may look good in picture but the benefits [link] of silk pillowcases are unrivaled, here’s a comparison post between polyester and silk pillowcases[link].

If it interest you, here’s my experience with a silk pillowcase [link] and silk nightcap [link].

What is the best way to tell polyester from silk

Remember earlier when I said polyester and silk burns differently? It may seem extreme but this is the most definitive way to identify real natural silk from synthetic polyester. I do not mean for you to burn the entire article of clothing, here’s how you can perform the burn test safely:

How to perform the burn test on silk

  1. Use scissors and tweezers to extract a few threads from the silk fabric
  2. Twist the threads together into a bunch and hold it with the tweezers
  3. Light the threads with a lighter, take note of the smell and watch for the burning pattern.

Ready for the verdict? Here is what you should be smelling and seeing if it is real, natural silk

Burnt silk smells like burnt human hair, if you are unsure how that smells like – do not burn your hair! Check to see if it smells like burnt polyester, which smells very much like burnt plastic or burnt paper.

Now, time to watch the flame, genuine silk will only burn when the source of flame is in contact with it. If you move the lighter away and it continues burning, bad news – it’s polyester. Polyester threads are highly flammable, catching fire and burning completely very quickly.

Take note of the residue as well, genuine silk’s residue will crumble into fine ash when you press on to it lightly while polyester often forms a misshapen blob that is not crushable.

Here’s a video to help you out:

Tell polyester from silk and purchase safely

With this chart now, if the silk item you are buying looks dubious and you are confused, whip this out and make sure it checks all of the properties of silk before buying!